Abstract

We construct and characterize a three terminal modulator, which operates in the microwave band at 8.0 GHz (λ = 3.7 cm) via interference of electromagnetic waves confined to a subwavelength structure. On/off ratios of more than 20 dB have been observed.
The modulator consists of intersecting linear arrays of closely spaced metal rods, similar to Yagi antenna aerials, that act as waveguides. The experimental results compare favorably with modeled modulation characteristics determined by full-field electromagnetic simulation. Analogies to potential optical frequency plasmonic devices, consisting of arrays of nanometer-scale metal particles, are discussed.